Which combination of sex chromosomes is found in the two kinds of human sperms?
A(22 + X) and (22 + Y)
B(44 + X) and (44 + Y)
C(22 + X) and (22 + X)
D(44 + XX) and (44 + XY)
Answer & Solution
Correct answer: A. (22 + X) and (22 + Y)
1. Diploid germ cells (44 + XY) in males divide by meiosis to form sperms.
2. Meiosis halves the number, so each sperm is haploid with 22 autosomes plus one sex chromosome.
3. The (44 + X) and (44 + Y) pair in B keeps the full count, so it is diploid and wrong.
4. The (44 + XX) and (44 + XY) pair in D are whole germ-cell or zygote counts, not sperms, so D is wrong.
5. Since the male is XY, two sperm types form: (22 + X) and (22 + Y).
6. Option C gives only X-bearing sperm, which describes oocytes, so it is ruled out, leaving A.
_Source: Balbharati (Maharashtra Board) Class 10 Science & Technology Part 2, Ch 3 "Life Processes in Living Organisms Part 2", p.39_
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